We totally thought you were nuts (except for that part about children needing mousse!) What are you talking about? No chocolate has disappeared from the market in the past 15 years. If anything, there's been a huge proliferation of new brands and varieties of chocolate.

Turns out, though, you're largely right.

The oh-so-trendy, oh-so-chic lust for ultra-dark chocolate that is 98.7643% chocolate liquor has apparently driven all the low-cacao chocolates off the market. Do not despair, however; we have a solution for you.

If you have a moment, you can see how our government classifies chocolate in this country. If you read carefully, you will be surprised to find "dark" chocolate appearing in two categories - Bittersweet and Sweet. (Actual names, it seems, are unimportant; it is the percentage of cacao in a piece of chocolate that matters. Also, as you can see, the word "dark" has no real meaning in the government's chocolate world.)

And as a practical matter, the government's entire Sweet-chocolate category (15% to 34% cacao, with little or no milk) has no meaning, either. We have not been able, after very much hunting, to find a sub-40% chocolate that is not a milk chocolate. Scharffenberger's semi-sweet chocolate is 62% cacao; Ghirardelli's, which is widely available in supermarkets, is 60%; and Guittard's lowest-cacao retail dark chocolate is 61% (although it has a dark chocolate at 54%, it is available only in food-service quantities). Its semisweet baking chips are at least 43% cacao. Nestle says it's Semi-Sweet Morsels are in the 40% range, but doesn't wish to disclose exactly where.

Clearly, while we were not paying attention, all the 60%/70%/80%/98.7643%+ chocolates pushed the sweeter dark chocolates off the shelves, and convinced chocolate makers that there is no money to be made in sweet dark chocolate. (There probably is sweet dark chocolate available somewhere, but we haven't been able to find it.)

Now, on to that solution. Since the difference between a high-percentage dark chocolate and a now extinct low-percentage dark chocolate is just sugar, you can make your own.

Start with the highest-sugar dark chocolate you can find - a "semi-sweet" somewhere in the 40% to 50% range, probably. Then use 25% to 35% less chocolate than called for in your recipe and add 1-1/2 teaspoons of granulated sugar for each ounce of chocolate you omit. If your recipe calls for 4 ounces of chocolate, use 3 ounces and 1-1/2 teaspoons of sugar.

You may have to make a few batches of mousse to find the right ratio of sugar to chocolate, but you should be able to recreate the mousse you remember and your daughter needs. You will want to dissolve the sugar in the melted chocolate or at some other step in the process, so that you don't encounter the graininess of undissolved sugar.

Addendum: Eureka! We found a sweet, dark, low-cacao-content chocolate - Santander's Chocolate Couverture 36% Cocoa Baking Bar. It still is a notch above the government's "sweet-chocolate" category, in with the bittersweets, but only by a measly 2%.